Normally, an IPv6-enabled system will also configure an IPv4 address. This is necessary because key parts of the Internet (in particular, residential ISPs) are years behind on their IPv6 deployment, so trying to run an IPv6 only stack is painful. Please explain why you believe you had only an IPv6 address.

roboto wrote:

dhcp in portage is set to version 4, instead of 6, which is stupid.

Please explain this statement. The DHCP server package version in Portage is version 4. The DHCPCD (client) package in Portage is version 6. Neither of these has any bearing on what IP versions are supported.

roboto wrote:

I disabled IPv6 entirely just now in my .config and dhcpcd still uses IPv6 addresses. Its output this boot was slightly different.

That log appears to cover several reboots, including ones from Tuesday, the day before your post. You did not indicate your local time at the time of the post, so we must guess which log entries were made with your IPv6-disabled kernel. I see one boot at 16:22 that tried to use IPv6. I see another boot at 16:33 that did not.

While that warning could be useful, remember that not all systems even have a kernel configuration available when the DHCP client is built, so the test needs to be optional. I have a bit of a sore point about the linux-info.eclass functions from a few years ago when packages kept needlessly dying because, while my kernel was configured correctly, they couldn't prove it, so they aborted.

Also, even when the configuration is available and shows AF_PACKET support, there's no guarantee that the package will be run on a well-configured system, only that the current build host is well-configured.

I have a bit of a sore point about the linux-info.eclass functions from a few years ago when packages kept needlessly dying because, while my kernel was configured correctly, they couldn't prove it, so they aborted.